The island of Taiwan is situated in one of the main paths of the north Western Pacific tropical cyclones. As Central Mountain Range is in center of the isolated island with a pick higher than 3,900 meters, therefore many interesting weather-topography interaction phenomena have been observed and documented. The forecast of the tropical cyclone's track and the rainfall and surface wind distribution are also complicated by the topography. To improve our understanding of the distribution of the surface wind speeds over the stations of Taiwan when tropical cyclones are in nearby, the wind speeds were collected and analyzed when a tropical cyclone was in the vicinity of Taiwan in 1961 to 2000. The analysis shows that the surface wind speed on the stations of western Taiwan generally reach their maximum when the center of the tropical cyclone was about 200km away from the station. In contrast, for the stations in east coast, their maximum surface wind speed occurred when the center the tropical cyclone was very near the station. For most of stations around the mountain, the larger surface wind speeds were also found when the tropical cyclone centers were in the other side of the mountain. Those are clear indication of mountain effect on the typhoon wind field. We will show more of the analysis results in the conference. We will also show our results on the evaluation of several simple statistical methods on the prediction of the strong surface winds for Taiwan area, in lead-times within 24 hours, when a tropical cyclone is approaching.
Corresponding author address: Dr. T.-C. Yeh yeh@cwb.gov.tw Tel: (886)-2-23491200; Fax: (886)-2-23491207 Central Weather Bureau 64 Kung Yuan Road, Taipei, Taiwan.
Supplementary URL: